The most interesting laptop of this period was the Duo’s successor, the PowerBook 2400c. It was a 4.4-pound PowerBook that was hard to find, didn’t sell particularly well, but was–like ...

Introduced in January 2008, it marked Apple's first serious attempt at a sub-notebook since the PowerBook 2400c of the mid-1990s. The MacBook Air takes thinness to a whole new level.